diff --git a/programs/ssl/ssl_server2.c b/programs/ssl/ssl_server2.c
index 25cdb40..87558f5 100644
--- a/programs/ssl/ssl_server2.c
+++ b/programs/ssl/ssl_server2.c
@@ -433,6 +433,15 @@
 #define USAGE_SERIALIZATION ""
 #endif
 
+#if defined(MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL)
+#define USAGE_TLS13_KEY_EXCHANGE_MODES \
+    "    tls13_kex_modes=%%s   default: all\n"     \
+    "                          options: psk_pure, psk_ephemeral, ephemeral_pure, ephemeral_all, psk_all, all\n"
+#else
+#define USAGE_TLS13_KEY_EXCHANGE_MODES ""
+#endif /* MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL */
+
+
 /* USAGE is arbitrarily split to stay under the portable string literal
  * length limit: 4095 bytes in C99. */
 #define USAGE1 \
@@ -496,18 +505,19 @@
 #define USAGE4 \
     USAGE_SSL_ASYNC                                         \
     USAGE_SNI                                               \
-    "    allow_sha1=%%d       default: 0\n"                             \
-    "    min_version=%%s      default: (library default: tls1_2)\n"       \
-    "    max_version=%%s      default: (library default: tls1_2)\n"     \
-    "    force_version=%%s    default: \"\" (none)\n"       \
+    "    allow_sha1=%%d       default: 0\n"                                   \
+    "    min_version=%%s      default: (library default: tls1_2)\n"           \
+    "    max_version=%%s      default: (library default: tls1_2)\n"           \
+    "    force_version=%%s    default: \"\" (none)\n"                         \
     "                        options: tls1_2, dtls1_2" TLS1_3_VERSION_OPTIONS \
-    "\n\n"                                                                \
-    "    force_ciphersuite=<name>    default: all enabled\n"            \
-    "    query_config=<name>         return 0 if the specified\n"       \
+    "\n\n"                                                                    \
+    "    force_ciphersuite=<name>    default: all enabled\n"                  \
+    USAGE_TLS13_KEY_EXCHANGE_MODES                                            \
+    "    query_config=<name>         return 0 if the specified\n"             \
     "                                configuration macro is defined and 1\n"  \
     "                                otherwise. The expansion of the macro\n" \
-    "                                is printed if it is defined\n"     \
-    USAGE_SERIALIZATION                                     \
+    "                                is printed if it is defined\n"           \
+    USAGE_SERIALIZATION                                                       \
     " acceptable ciphersuite names:\n"
 
 #define ALPN_LIST_SIZE  10